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Fusion energy: Progress, partnerships, and the path to deployment
Over the past decade, fusion energy has moved decisively from scientific aspiration toward a credible pathway to a new energy technology. Thanks to long-term federal support, we have significantly advanced our fundamental understanding of plasma physics—the behavior of the superheated gases at the heart of fusion devices. This knowledge will enable the creation and control of fusion fuel under conditions required for future power plants. Our progress is exemplified by breakthroughs at the National Ignition Facility and the Joint European Torus.
Shin Chang, George H. Miley, Clifford E. Singer
Fusion Science and Technology | Volume 33 | Number 4 | July 1998 | Pages 387-397
Technical Paper | doi.org/10.13182/FST98-A39
Articles are hosted by Taylor and Francis Online.
The influence of controlled sawteeth on thermal helium exhaust is explored using the BALDUR 1½-dimensional transport code for an ARIES-I-type plasma. Sawteeth are shown to be useful for removing thermal helium from the central region to the outer region of a tokamak plasma. Outer region transport enhancement is found essential for removing the ash from the outer region. It is found that the optimal sawtooth period to give the minimum thermal helium level (or maximum fusion power) is several times larger than the fast alpha-particle slowing-down time for an ARIES-I-type driven plasma. With a sawtooth period of ~5 s and helium transport selectively enhanced by one order of magnitude relative to the diffusion of hydrogenic ions, the fusion power increases ~30% compared to the case without sawteeth/without enhancement. It is also found that sawteeth combined with outer region transport enhancement have the potential to advantageously reduce the helium concentration.